MOUNT RAINIER NATIONAL PARK, Wash. (AP) — A Mount Rainier National Park ranger was fatally shot following a New Year's Day traffic stop, and the 368-square-mile park in Washington state was closed as dozens of officers searched for the armed gunman over snowy and rugged terrain.Pierce County Sheriff's spokesman Ed Troyer said late Sunday afternoon Benjamin Colton Barnes, a 24-year-old believed to have military experience and survivalist skills, was a "strong person of interest" in the slaying of Margaret Anderson. Authorities recovered Barnes' vehicle, which had weapons and body armor inside, Troyer said.Barnes was also a suspect in the early Sunday morning shooting of four people at a house party south of Seattle, police said.Authorities believed the gunman was still in the woods, with weapons. They asked people to stay away from the park, and for those already inside to leave."We do have a very hot and dangerous situation," Troyer said.Kevin Bacher, a spokeswoman for the park, said about 125 people were still at the visitor's center Sunday night along with five law enforcement officers protecting the facility. He said crews had considered removing them in armored vehicles, but decided not to take any risk.Jason Simpson, 29, of Kent, said his parents were still trapped at the visitor's center after traveling to the mountain for a day hike. His parents were able to make a call explaining their situation, and Simpson drove to the park entrance to wait."It's very distressing," Simpson said.Sgt. Cindi West, King County Sheriff's spokesperson, said late Sunday that Barnes was connected to an early-morning shooting at a New Year's house party in Skyway, Wash., south of Seattle that left four people injured, two critically.At Mount Rainier around 10:20 a.m. Sunday, Bacher said the gunman had sped past a checkpoint used to assess the tires of visitors. One ranger began following him while Anderson eventually blocked the road to stop the driver.Before fleeing, the gunman fired shots at both Anderson and the ranger that trailed him, but only Anderson was hit, Bacher said.A helicopter was able to identify tracks in the snow, Bacher said, and authorities are pursuing that trail. It was possible that searchers may wait until morning to continue the effort."We do not know what resources the shooter has. We're not sure what we're up against," Bacher said. "We know that he has a weapon, but we don't know how many."About 150 officers, including officials from the Washington State Patrol, U.S. Forest Service and FBI, were on the mountain. They had not made contact with the gunman and did not know where he was, Troyer said.A military-style, armored vehicle was seen as police deployed resources into the evening.Authorities said earlier that Anderson's body had been removed from the park, but Troyer said police have been unable to get to her because of concern over potentially being in the line of fire.Park superintendent Randy King said Anderson is a mother of two young daughters who has served as a park ranger for about four years. King said Anderson's husband also was working as a ranger elsewhere in the park at the time of the shooting."It's just a huge tragedy — for the family, the park and the park service," he said.Adam Norton, a neighbor of Anderson's in the small town of Eatonville, Wash., said the ranger's family moved in about a year ago. He said they were not around much, but when they were Norton would see Anderson outside with her girls."They just seemed like the perfect family," he said.The town of about 3,000 residents, which is a logging community overlooking Mount Rainier, is very close knit, he said."It's really sad right now," Norton said. "We take care of each other."It has been legal for people to take loaded firearms into Mount Rainier since 2010, when a controversial federal law went into effect that made possession of firearms in national parks subject to state gun laws.The shooting occurred on an unseasonably sunny and mild day. The park, which offers miles of wooded trails and spectacular vistas from which to see 14,410-foot Mount Rainier, draws between 1.5 million and 2 million visitors each year.The Longmire station served as headquarters when the national park was established in 1899. Park headquarters have moved but the site still contains a museum, a hotel, restaurant and gift shop, which are open year-round.